The "x" is what you specified. You could replace that with a cell reference and whatever value is in that cell will be matched instead of Xs. You could use a radio button to control the content of that cell.

=INDEX($M$5:$M$24,MATCH($A$1,$K$5:$K$24,0))

INDEX(MATCH() is a standard technique. Read up on it here:
http://www.contextures.com/xlFunctions03.html